1. Field of the Invention
The present invention relates to an amplifier circuit.
2. Description of the Related Art
Japanese Patent Laid-Open No. 5-226948 discloses a multiple output amplifier including a constant current source, an amplifier input stage, a level shift stage, and a plurality of output circuits. In this multiple output amplifier, the plurality of output circuits share the constant current source, amplifier input stage, and level shift stage, thereby suppressing an increase in chip area.
The multiple output amplifier disclosed in Japanese Patent Laid-Open No. 5-226948 does not stop the operation of an output circuit not in use. When a load is connected to the output circuit not in use, the output circuit not in use may adversely affect an output circuit in use in a way such as a crosstalk. In addition, power is consumed by a bias current for operating the output circuit not in use.